On Wed, Nov 27, 2013 at 11:43:44AM -0800, Junio C Hamano wrote: > Nick Townsend <nick.towns...@mac.com> writes: > > * The .gitmodules file can be dirty (easy to flag, but should we > > allow archive to proceed?) > > As we are discussing "archive", which takes a tree object from the > top-level project that is recorded in the object database, the > information _about_ the submodule in question should come from the > given tree being archived. There is no reason for the .gitmodules > file that happens to be sitting in the working tree of the top-level > project to be involved in the decision, so its dirtyness should not > matter, I think. If the tree being archived has a submodule whose > name is "kernel" at path "linux/" (relative to the top-level > project), its repository should be at .git/modules/kernel in the > layout recent git-submodule prepares, and we should find that > path-and-name mapping from .gitmodules recorded in that tree object > we are archiving. The version that happens to be checked out to the > working tree may have moved the submodule to a new path "linux-3.0/" > and "linux-3.0/.git" may have "gitdir: .git/modules/kernel" in it, > but when archiving a tree that has the submodule at "linux/", it > would not help---we would not know to look at "linux-3.0/.git" to > learn that information anyway because .gitmodules in the working > tree would say that the submodule at path "linux-3.0/" is with name > "kernel", and would not tell us anything about "linux/". > > > * Users can mess with settings both prior to git submodule init > > and before git submodule update. > > I think this is irrelevant for exactly the same reason as above. > > What makes this tricker, however, is how to deal with an old-style > repository, where the submodule repositories are embedded in the > working tree that happens to be checked out. In that case, we may > have to read .gitmodules from two places, i.e. > > (1) We are archiving a tree with a submodule at "linux/"; > > (2) We read .gitmodules from that tree and learn that the submodule > has name "kernel"; > > (3) There is no ".git/modules/kernel" because the repository uses > the old layout (if the user never was interested in this > submodule, .git/modules/kernel may also be missing, and we > should tell these two cases apart by checking .git/config to > see if a corresponding entry for the "kernel" submodule exists > there); > > (4) In a repository that uses the old layout, there must be the > repository somewhere embedded in the current working tree (this > inability to remove is why we use the new layout these days). > We can learn where it is by looking at .gitmodules in the > working tree---map the name "kernel" we learned earlier, and > map it to the current path ("linux-3.0/" if you have been > following this example so far). > > And in that fallback context, I would say that reading from a dirty > (or "messed with by the user") .gitmodules is the right thing to > do. Perhaps the user may be in the process of moving the submodule > in his working tree with > > $ mv linux-3.0 linux-3.2 > $ git config -f .gitmodules submodule.kernel.path linux-3.2 > > but hasn't committed the change yet. > > > For those reasons I deliberately decided not to reproduce the > > above logic all by myself. > > As I already hinted, I agree that the "how to find the location of > submodule repository, given a particular tree in the top-level > project the submodule belongs to and the path to the submodule in > question" deserves a separate thread to discuss with area experts.
FYI, I already started to implement this lookup of submodule paths early this year but have not found the time to proceed on that yet. I am planning to continue on that topic soonish. We need it to implement a correct recursive fetch with clone on-demand as a basis for the future recursive checkout. During the work on this I hit too many open questions. Thats why I am currently working on a complete plan so we can discuss and define how this needs to be implemented. It is an asciidoc document which I will send out once I am finished with it. Cheers Heiko  http://article.gmane.org/gmane.comp.version-control.git/217020  https://github.com/hvoigt/git/wiki/submodule-fetch-config -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html